CN103475583B

CN103475583B - The method and apparatus for removing medium education forwarding-table item

Info

Publication number: CN103475583B
Application number: CN201210186577.7A
Authority: CN
Inventors: 郝卫国; 厉益舟; 李振斌; 阴元斌; 丁成龙
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2012-06-07
Filing date: 2012-06-07
Publication date: 2017-11-17
Anticipated expiration: 2032-06-07
Also published as: EP2852108A1; US9762410B2; WO2013182031A1; US20150092602A1; CN103475583A; EP2852108B1; EP2852108A4; US20170331640A1; US10277418B2

Abstract

The invention provides a method and equipment for clearing MAC forwarding entries. The method includes that the first RB detects that the topology of the network accessed by the local terminal changes; the first RB sends a first message to the second RB, so that the second RB clears the corresponding transfer In the published item, the second RB refers to an RB configured with at least one VLAN same as that of the first RB. In the embodiment of the present invention, after the topology of the network accessed by the local terminal changes, the MAC forwarding table entries of the related equipment in the entire network can be cleared in time to avoid forwarding errors.

Description

Method and equipment for clearing media access control forwarding table item

Technical Field

The present invention relates to network communication technologies, and in particular, to a method and a device for clearing a Media Access Control (MAC) forwarding table.

Background

Transparent interconnection of Lots of Links (TRILL) protocol is a routing protocol based on link state calculation on a two-layer network, a device running the TRILL protocol is called a Route Bridge (RB), and a network composed of RBs is called a TRILL network (TRILL Campus). The large two-layer networking can be realized through TRILL, and the defects of low bandwidth utilization rate, slow convergence time and the like of the traditional two-layer network are overcome.

A conventional two-layer local ethernet (native ethernet) may access the TRILL network, and generally, in order to improve the reliability of the access network, the TRILL network is accessed in a Multi-Homing (Multi-Homing) manner. If the network topology accessed by the terminal (End Station, ES) is switched, the RB accessed by the local terminal device is switched, and if the MAC forwarding table entry on the remote RB for storing the correspondence between the MAC address and the alias (nickname) of the access (Ingress) RB cannot be cleared in time, the remote RB forwards the MAC forwarding table entry through the old MAC forwarding table entry, which may result in a forwarding failure.

Disclosure of Invention

The embodiment of the invention provides a method and equipment for clearing an MAC forwarding table entry, which are used for clearing the MAC forwarding table entry in time after the network topology accessed by a local terminal changes, so that the forwarding is prevented from being obstructed.

In one aspect, a method for clearing an MAC forwarding table entry is provided, including:

the first RB detects that the network topology accessed by the local terminal changes;

the first RB sends a first message to a second RB so that the second RB clears a corresponding MAC forwarding table entry after receiving the first message, wherein the second RB is an RB at least configured with a VLAN which is the same as that of the first RB.

In another aspect, a method for clearing an MAC forwarding table entry is provided, including:

a second RB receives a first message, wherein the first message is sent after the first RB detects that the network topology accessed by a local terminal changes, and the second RB is configured with at least one VLAN (virtual local area network) same as the first RB;

and the second RB clearing the corresponding MAC forwarding table entry according to the first message.

In one aspect, an apparatus for clearing an MAC forwarding table entry is provided, including:

the detection module is used for detecting that the network topology accessed by the local terminal changes;

a sending module, configured to send a first packet to a second RB, so that the second RB clears a corresponding MAC forwarding table after receiving the first packet, where the second RB is an RB that is configured with at least one VLAN that is the same as the first RB.

In another aspect, an apparatus for clearing a MAC forwarding table entry is provided, including:

the receiving module is used for receiving a first message, wherein the first message is sent by a first RB after the change of a network topology accessed by a local terminal is detected;

and the processing module is used for clearing the corresponding MAC forwarding table entry according to the first message.

According to the technical scheme, after the network topology accessed by the local terminal is changed through the first RB, the second RB is notified by the first message, the MAC forwarding table entry on the second RB can be cleared quickly, the TRILL network data flow is triggered to be converged quickly, and smooth forwarding of the data flow is guaranteed.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive labor.

Fig. 1 is a flowchart illustrating an embodiment of a method for clearing an MAC forwarding entry according to the present invention;

FIG. 2 is a schematic diagram of a structure for implementing destruction by AF mechanism in the present invention;

FIG. 3 is a schematic structural diagram of the present invention illustrating the destruction implemented by simulating an STP root bridge using an edge RB;

FIG. 4 is a diagram illustrating an example of an RB channel packing format according to the present invention;

FIG. 5 is a diagram illustrating another packing format of RB channels in the present invention;

fig. 6 is a flowchart illustrating another embodiment of a method for clearing MAC forwarding entries according to the present invention;

FIG. 7 is a diagram of the initial communication path corresponding to FIG. 6;

fig. 8 is a diagram of a communication path after handover corresponding to fig. 6;

FIG. 9 is a diagram illustrating the number of packages of RB channels corresponding to FIG. 6;

fig. 10 is a flowchart illustrating another embodiment of a method for clearing MAC forwarding entries according to the present invention;

FIG. 11 is a diagram of the initial communication path corresponding to FIG. 10;

fig. 12 is a diagram illustrating a communication path after handover corresponding to fig. 10;

FIG. 13 is a diagram illustrating the number of packages of RB channels corresponding to FIG. 10;

fig. 14 is a schematic structural diagram of an apparatus for clearing MAC forwarding entries according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of an apparatus for clearing a MAC forwarding table entry according to another embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Fig. 1 is a flowchart illustrating an embodiment of a method for clearing an MAC forwarding table entry according to the present invention, including:

step 11: the first RB detects that the network topology to which the local terminal is accessed changes.

Wherein the first RB may refer to an edge RB of the TRILL network. Under the condition of multi-homing networking, in order to avoid the problem of broadcast storm caused by the fact that a plurality of access RBs can transmit data traffic, the access link of the multi-homing networking can be damaged, so that a traditional two-layer network can only be accessed into a TRILL network through one access link.

The destruction may be implemented by an Application Forwarders (AF) mechanism in the TRILL Protocol, or implemented by an edge RB simulation Spanning Tree Protocol (STP) root bridge, where STP is a universal STP, Rapid Spanning Tree Protocol (RSTP), or multiple-Instance Spanning Tree Protocol (MSTP).

Referring to fig. 2, for a structural schematic diagram of implementing a disruption for an AF mechanism, a TRILL protocol is run between RB1 and RB3, message interaction is performed through a TRILL interaction message (specifically, a TRILL Hello message), one of RB1 and RB3 is designated as a Forwarder (Forwarder) corresponding to some Virtual Local Area Networks (VLANs), and the other RB cannot forward data traffic in the VLAN, so that a disruption can be implemented. Referring to fig. 2, the link between the Bridge device (Bridge) and RB3 is broken as an example.

Referring to fig. 3, a structural diagram for simulating STP root bridge implementation destruction for edge RB, referring to fig. 3, assuming that RB1 and RB2 access the same STP network, RB1 and RB2 externally present the same bridge ID and bridge priority, where the bridge priority configuration is the highest. For the STP network composed of switches S1, S2, S3 and S4 accessed below, RB1 and RB2 correspond to a root bridge device, and in this embodiment, the port connected to S2 on the S3 device is blocked (block), and the port connected to S1 on the S2 device is blocked (block).

For a scenario in which the AF mechanism is damaged, when the edge RB detects AF handover, specifically, non-AF handover is changed into AF, which may be understood as a change in network topology accessed by the local terminal. When a link failure occurs between RB1 and the bridge device in fig. 2, the RB accessed by the terminal is switched from RB1 to RB3, which can be understood as a change in the network topology accessed by the local terminal.

For a scenario that the edge RB simulates an STP root bridge to implement destruction, when the edge RB receives a Topology Change Notification (TCN) message from an access port facing a terminal, it can be determined that a network Topology to which the terminal is accessed is switched. The STP network initial blocking ports for TRILL access as in fig. 3 are located on the S2 and S3 devices at the port where S2 is connected to the S1 device and at the port where S3 is connected to the S2 device, respectively. The ES1 to the ES5 all belong to the same VLAN, when a link between the S1 and the S3 fails, a port connected with the S2 on the S3 equipment is changed from a blocking state to a Forwarding (Forwarding) state, so that the S3 generates a TCN message, the TCN message is sent to the S2 through the link between the S3 and the S2, and the S2 then sends the TCN message to the RB 2. Therefore, when the access port of the RB2 receives the TCN message, the change of the network topology accessed by the local terminal can be determined.

Step 12: the first RB sends a first message to a second RB so that the second RB clears a corresponding MAC forwarding table entry after receiving the first message, wherein the second RB is an RB at least configured with a VLAN which is the same as that of the first RB.

After determining that the network topology to which the local terminal is accessed changes, the first RB may send a first packet to the second RB.

For example, the VLAN corresponding to the first RB comprises VLAN 1-VLAN 10, and if the VLAN corresponding to a RB other than the first RB comprises at least one of VLAN 1-VLAN 10, the RB is the second RB.

Optionally, the first message may be a MAC flush (MAC flush) message or a TCN message.

For example, referring to fig. 2, for a scenario where the AF mechanism is damaged, RB3 may send a MAC flush packet to RB 2; or, referring to fig. 3, for a scenario in which the edge RB simulates an STP root bridge to implement destruction, RB2 sends a MAC flush message to RB3 and RB4, and RB2 sends a TCN message to RB 1.

The first packet may be sent through a data channel, for example, an RB channel (RBridge channel). The first message may be sent in a multicast or broadcast manner, if the first message is in a multicast manner, a destination alias (nickname) in the TRILL Header is a nickname of a tree root distributed in the TRILL network, and if the first message is in a unicast manner, the destination nickname in the TRILL Header is a nickname of a destination RB (for example, the nickname of RB 1).

Specifically, when the multicast mode is used for transmission, all the second RBs and the first RBs need to be on the same distribution tree or a pruned distribution tree, and the first RB only needs to transmit one MAC clear message or TCN message through a multicast TRILL data channel corresponding to the distribution tree or the pruned distribution tree. When the unicast mode is used for sending, all second RBs are obtained in advance by searching a Link State Data Base (LSDB) of the whole network, and then an MAC clearing message or a TCN message is sent to each second RB through a unicast TRILL channel. Taking the RB2 to send the first packet as an example, if the first packet is sent in a multicast manner, the RB2 only needs to send one copy of the first packet; if the unicast mode is adopted, the RB2 needs to send a first packet to each remote RB device. For multicast transmission, the transmission may be performed through a shared distribution tree, or may be performed through a pruned distribution tree based on a certain VLAN, and it needs to be ensured that all the edge RBs to be transmitted are leaf nodes of the distribution tree or the pruned distribution tree.

When the first packet is sent by unicast or multicast through a distribution tree, the encapsulation format of the RBridge channel may be as shown in fig. 4, and includes an external Ethernet Header (out Ethernet), a Trill Header (Trill Header), an internal Ethernet Header (Inner Ethernet Header), an OAM channel Header (OAM channel Header), and a payload (payload). Different from the prior art, two channel protocol types are newly added in the OAM channel head, which indicates that the payload part is a TCN message or a MACflush message.

When the first packet is multicast-transmitted through the pruned distribution tree, the encapsulation format of the RBridge channel may refer to fig. 5, where fig. 5 takes as an example that all edge RBs to be transmitted are added to the VLAN10, and at this time, it is equivalent to fig. 4 that the VLAN10 field needs to be added.

Optionally, the first RB may also send the first packet to each RB of the same VLAN, and at this time, the RB that receives the first packet may ignore and not process the first packet.

The MAC forwarding table entry includes a correspondence between a terminal MAC address and an alias (nickname) of an access rb (access rb). Where the access RB is an edge RB that forwards data traffic, such as RB1 in fig. 2 or fig. 3, above.

In addition, after the first RB detects that the network topology to which the local terminal is accessed changes, the local MAC forwarding table entry is cleared.

In this embodiment, after the network topology of the first RB accessed to the local terminal changes, the first packet is notified to the second RB, so that the MAC forwarding table entry on the second RB device can be quickly cleared, and rapid convergence of TRILL network data traffic is triggered.

Fig. 6 is a flowchart illustrating another embodiment of the method for clearing the MAC forwarding table entry according to the present invention, where the present embodiment takes an application scenario as follows: and the interconnection of the traditional two-layer network and the TRILL network is realized through an AF mechanism in the TRILL protocol. The embodiment comprises the following steps:

step 61: the two ESs communicate through an initial communication path.

Referring to fig. 7, the initial communication paths for two ESs, ES1 and ES2, ES2 and ES1, respectively, are: ES2 → RB2 → RB1 → Bridge → ES1, that is, the data packet forwarding path shown by the thick solid line, the thick solid line in the following figures has the same meaning.

Step 62: RB3 detects that AF is switched.

For example, AF may switch after configuration or link failure between RB1 and Bridge. RB3 may detect the AF handover.

And step 63: the RB3 sends a MAC flush (MAC flush) message to RB2, where the message includes VLAN information corresponding to the AF after the switching.

Each RB can determine VLAN information corresponding to itself, and therefore, after AF switching, the switched AF, for example, RB3 described above, can obtain VLAN information corresponding to itself and carry the VLAN information in the MACflush message.

The VLAN information may be a VLAN list (VLAN list) or a VLAN bitmap (VLAN bitmap) where each bit represents a VLAN, which may save space relative to the VLAN list.

In order to more accurately remove the MAC forwarding entry corresponding to the VLAN, the MAC removal message may further include one or more MAC addresses or aliases (nicknames) in addition to the VLAN information, and is configured to instruct the second RB to remove the MAC forwarding entry matching the VLAN information and the MAC address, or remove the MAC forwarding entry matching the VLAN and the aliases. That is, all the MAC forwarding entries corresponding to the VLAN indicated by the clear VLAN information include the MAC forwarding entry of the MAC address or the alias.

And when the VLAN information and the nickname are contained, the second RB is used for indicating the second RB to clear the MAC forwarding table entry matched with the VLAN and the nickname. Under an AF mechanism, the nickname is a nickname of an original RB accessed by the local terminal, for example, in fig. 7, the nickname is a nickname of an RB1 device, and an AF is switched from RB1 to RB3, and a second RB (RB 2) needs to be notified to remove an MAC entry accessed to RB 1; under the condition that an edge RB simulates an STP root bridge, nicknames of all RBs accessed to the same STP domain, for example, in fig. 12, after the topology of an access network changes, a second RB needs to be notified to clear MAC entries accessed to the RBs RB1 and RB2, where the nicknames are nicknames of devices RB1 and RB 2. In this case, the MAC flush packet includes contents: (VLAN 1, nickname list), (VLAN 2, nickname list) …. The second RB clears only the MAC forwarding entries in the specified VLAN learned from the RBs corresponding to these nicknames.

If the MAC address corresponding to the terminal of the local access network is definitely known, the MAC flush packet may also be used to instruct the second RB to clear the corresponding MAC forwarding entry by specifying the VLAN information and the MAC address. In this case, the MAC flush packet includes contents: (VLAN 1, MAC address list), (VLAN 2, MAC address list) …. The second RB clears only MAC forwarding entries in these specified VLANs that contain the specified MAC address.

The MAC flush message may be sent in a data Channel, which may be an RBridge Channel. Referring to fig. 9, a schematic diagram of a format for sending an MAC flush packet by using a data channel is shown.

In addition, the MAC flush message can be sent in a unicast or multicast mode. The format of the data channel used in unicast or multicast may be referred to fig. 4 or fig. 5.

Step 64: after receiving the MAC flush message, RB2 clears the MAC forwarding table entry corresponding to the VLAN included in the MAC flush message.

Specifically, the forwarding chip of RB2 sends the MAC flush message to the CPU control plane, and the CPU control plane removes the MAC forwarding entry in the corresponding VLAN according to the VLAN information in the MAC flush message. For example, the MAC flush message includes VLAN1 and VLAN2, and after receiving the MAC flush message, RB2 removes the MAC forwarding entry corresponding to VLAN1 and the MAC forwarding entry corresponding to VLAN 2.

Optionally, RB3 may also send the MAC flush packet to RB1, and RB1 removes the MAC forwarding entry corresponding to the VLAN after receiving the MAC flush packet. Alternatively, RB1 may also clear its MAC forwarding table entry after detecting AF handover. Alternatively, RB1 may also wait for the aging of the MAC forwarding entry to effect the clearing of the MAC forwarding entry.

Further, after the MAC forwarding table entry is cleared, a new MAC forwarding table entry may be learned in the following manner, so as to update the MAC forwarding table entry in time.

ES2 sends a unicast data packet to RB2, after RB2 receives the two-layer unicast data packet, since the MAC forwarding table entry has been cleared, RB2 will process the packet as an unknown unicast packet, and send the packet to RB1 and RB3 through a distribution tree.

After receiving the message, RB3 carries out TRILL decapsulation, learns the source MAC of ES2, then sends the message to Bridge through the access port, and the Bridge also learns the source MAC of ES 2. Bridge then sends the message to ES 1.

The ES1 responds after receiving the unicast data message of ES 2. The response message reaches ES2 through a unicast message forwarding path, where the forwarding path is ES1- > Bridge- > RB3- > RB2- > ES2, and the RB2 learns the source MAC of ES1, and the source Nickname is the Nickname of RB 3. Similarly, the bridge device may also learn the MAC address of ES2 and the MAC address of ES1 during the unicast data message and the response message.

The subsequent ES2 and ES1 can be interworked through a unicast flow.

In summary, after the AF is switched, referring to fig. 8, the communication path after switching is switched to: ES2 → RB2 → RB3 → Bridge → ES 1.

In this embodiment, after the AF is switched, the switched AF (specifically RB 3) sends an MAC flush message to a second RB (specifically RB 2), and RB2 removes the MAC forwarding entry after receiving the MAC flush message, so that the MAC forwarding entry on the RB2 device can be quickly removed, and the TRILL network data traffic is triggered to quickly converge.

Fig. 10 is a flowchart illustrating another embodiment of the method for clearing the MAC forwarding table entry according to the present invention, where the present embodiment takes an application scenario as follows: and simulating an STP root bridge by the edge RB equipment to realize the interconnection scene of the STP network and the TRILL network. The embodiment comprises the following steps:

step 101: the two ESs communicate through an initial communication path.

Referring to fig. 11, the STP network initial blocking ports for TRILL access are located on the S2 and S3 devices at the port where S2 is connected to the S1 device and the port where S3 is connected to the S2 device, respectively. The ESs 1 to ES5 all belong to the same VLAN.

ES5 communicates through S4 → S1 → S3 and ES1, and ES3 communicates through RB3 → RB1 → S1 → S3 and ES 1.

Step 102: the access to the STP topology is switched.

When the access STP topology is switched, for example, when a link between S1 and S3 fails, the blocking port of S3 (S3 → S2) changes to a Forwarding state, S3 clears the local MAC Forwarding table entry, generates a TCN packet, and sends the TCN packet to S2; and S2, after receiving the TCN message, clearing the local MAC forwarding table entry, and then sending the TCN message to the RB 2. After receiving the TCN message, RB2 sends the TCN message to an STP protocol component in RB2 for processing, and the STP protocol component will clear the MAC forwarding table entry in the local forwarding chip, send the TCN message to other RBs in the same STP domain, and send the MAC flush message to other RBs not in the same STP domain. That is, RB2 sends the TCN message to RB 1; RB2 sends MAC flush messages to RB3 and RB4, which contain VLAN information.

Both the TCN packet and the MAC flush packet may be sent by using an RBridge channel, a schematic structural diagram of the MAC flush packet sent by using an RBridge channel may refer to fig. 9, and a schematic structural diagram of the TCN packet sent by using an RBridge channel may refer to fig. 13.

In addition, it should be noted that, under the condition of STP or RSTP, in this embodiment, removing the local MAC forwarding entry refers to removing MAC forwarding entries in all VLANs added to the access port facing the local terminal; under the condition of MSTP, each RB may correspond to multiple MSTP instances, the local part of the RB may configure the corresponding relationship between the MSTP instances and the VLAN, the received TCN message may include information of the instances, and after receiving the TCN message, the RB may clear the MAC forwarding table entry of the VLAN corresponding to the instance.

Namely, step 102 may be followed by step 103 and step 104, or alternatively, by steps 105 to 109.

Step 103: RB2 generates a MAC flush (MAC flush) message to RB3 and RB4, wherein the MAC flush message contains VLAN information;

step 104: and after receiving the MAC flush message, RB3 and RB4 remove the MAC forwarding table entry corresponding to the VLAN information contained in the MAC flush message.

Step 105: RB2 sends TCN message to RB 1;

step 106: and after receiving the TCN message, the RB1 clears the local MAC forwarding table entry.

For example, in MSTP, after receiving the TCN packet, RB1 may clear the MAC forwarding entry of the VLAN corresponding to the instance indicated by the instance information included in the TCN packet. Under the condition of STP or RSTP, after receiving the TCN message, the RB1 clears the MAC forwarding entries in all VLANs added to the access port facing the local terminal, for example, if the access VLAN configured on the access port is 100 to 200, then after receiving the TCN message, the MAC forwarding entries in the VLANs 100 to 200 need to be cleared, and the VLANs configured by the access ports corresponding to the RBs in the same STP domain need to be consistent.

And after receiving the MAC flush message, RB3 and RB4 remove the MAC forwarding table entry corresponding to the VLAN information contained in the MAC flush message.

Further, after receiving the TCN message, RB1 may also instruct other switch devices in the same STP domain to clear the MAC forwarding table entry. Namely, it may further include:

step 107: RB1 sends a TCN message to S1.

Step 108: and after receiving the TCN message, the S1 clears the local MAC forwarding table entry and sends the TCN message to the S4.

Step 109: and S4, after receiving the TCN message, clearing the local MAC forwarding table entry.

ES3 and ES1 subsequent communication procedures:

the ES3 subsequently communicates with the ES1, the RB3 receives the two-layer unicast data message of the ES3, and since the local MAC table entry is cleared, the two-layer data message can be sent to all RB devices including RB2 devices as an unknown unicast message, and the RB2 device learns the MAC of the ES 3. Meanwhile, RB2 will send the message to ES1 through the access port, ES1 will respond after ES1 receives.

RB2 receives the response message of ES1 from the access port, because the destination MAC is the MAC of ES3, unicast TRILL encapsulation is carried out by searching a local MAC forwarding table, then the message is sent to RB3, RB3 learns the MAC of ES1, and simultaneously the message is sent to ES 3. The subsequent communication between the ES3 and the ES1 is performed in a unicast mode, and the message forwarding path is changed into RB3- > RB2- > S2- > S3 instead of the original RB3- > RB1- > S1- > S3.

If the access STP topology change event is not timely notified to RB3, RB3 device still maintains the old MAC entry of ES1, and the source Nickname is still the Nickname of RB1 device, so that the unicast message from ES3 to ES1 will be sent to RB1 device, but due to the link failure from S1 to S3, RB1 cannot send the message to ES1, and the forwarding is not passed. Subsequently, the ES3 can communicate with the ES1 normally only after the MAC on the RB3 device ages naturally, which is a relatively long aging time, typically a few minutes. Therefore, the rapid convergence of the TRILL network data forwarding can be realized through the scheme.

ES5 and ES1 subsequent communication procedures:

if the ES5 subsequently communicates with ES1, after S1 receives the unicast data packet of ES5, ES5 will process the unicast data packet as an unknown unicast packet and send it to RB1 because the MAC entry on ES5 is cleared.

After RB1 receives the unicast data packet, since the MAC forwarding table has been cleared, it is treated as an unknown unicast packet. The message is sent to all other RBs through the multicast distribution tree, including RB 2.

After receiving the data message, RB2 decapsulates TRILL data, learns the source MAC of ES5, and then sends it to S2.

S2 is sent to S3, S3 is sent to ES 1.

ES1 will send the response message to ES5 through S3- > S2- > RB2- > RB1- > S1, RB1 will learn the source MAC of ES1, and the source Nickname is the Nickname of RB2 device. Thus, after the accessed STP topology is changed, normal communication can be carried out between the ES5 and the ES 1. If the topology change event is not sensed by S4 and S1, the old MAC entry is still maintained on the S4 and S1 devices, and the messages from ES5 to ES1 are sent to ES1 through S4- > S1- > S3, but due to the failure of ES1- > ES3, the forwarding is not successful.

For example, referring to fig. 12, after the access network topology changes, the ES3 finally communicates through RB3 → RB2 → S2 → S3 and ES 1.

In this embodiment, when the network topology accessed by the local terminal changes, all nodes of the whole TRILL network can clear the MAC forwarding table entry in time, so as to update in time, thereby triggering fast convergence of data forwarding. In addition, in this embodiment, when the first RB is used to simulate an STP root bridge to perform a destruction, the TCN packet may be flooded to the entire access network, so that the MAC entry of the entire access network device is quickly cleared, and the access network traffic is triggered to quickly converge.

Fig. 14 is a schematic structural diagram of an embodiment of an apparatus for clearing a MAC forwarding table entry according to the present invention, where the apparatus may be an edge RB of a TRILL network, and the apparatus includes a detecting module 141 and a sending module 142; the detecting module 141 is configured to detect that a network topology accessed by the local terminal changes; the sending module 142 is configured to send the first packet to a second RB, so that the second RB clears the corresponding MAC forwarding table entry after receiving the first packet, where the second RB is an RB configured with at least one VLAN that is the same as the first RB.

Optionally, the detection module is specifically configured to: and after detecting that the equipment is changed from non-AF to AF under the appointed forwarder AF mechanism, determining that the network topology accessed by the local terminal is changed.

Optionally, the first message sent by the sending module is an MAC clear message, where the MAC clear message includes VLAN information and indicates the second RB to clear an MAC forwarding entry corresponding to the VLAN information.

Optionally, the MAC clear packet may further include one or more MAC addresses or aliases, and instruct the second RB to clear the MAC forwarding entries including the MAC addresses or aliases in all the MAC forwarding entries corresponding to the VLAN information.

Optionally, the detection module is specifically configured to: and under a first RB simulation STP root bridge mechanism, when receiving a TCN message from an access port facing a local terminal, determining that the network topology accessed by the terminal is switched.

Optionally, the first message sent by the sending module is a TCN message, and instructs the second RB to remove a local MAC forwarding table entry, where in an STP or RSTP scenario, the first message instructs the second RB to remove MAC forwarding table entries in all VLANs added to an access port facing a local terminal, and in an MSTP scenario, the first message includes instance information and instructs the second RB to remove an MAC forwarding table entry of a VLAN corresponding to the instance information; or,

the first message sent by the sending module is an MAC clearing message, the MAC clearing message contains VLAN information, and the second RB is indicated to clear an MAC forwarding table entry corresponding to the VLAN information.

Optionally, the first packet is sent through a data channel, and the data channel is an RB channel.

Optionally, the first packet is sent in a multicast mode or a unicast mode, where the RB channel is in a multicast TRILL data packet encapsulation format when the first packet is sent in the multicast mode, and the RB channel is in a unicast TRILL data packet encapsulation format when the first packet is sent in the unicast mode.

In this embodiment, after the network topology accessed by the local terminal changes, the second RB is notified with the first message, so that the MAC forwarding table entry on the second RB device can be quickly cleared, and the TRILL network data traffic is triggered to be quickly converged.

Fig. 15 is a schematic structural diagram of another embodiment of the apparatus for clearing MAC forwarding entries according to the present invention, where the apparatus may be a remote RB, and the apparatus includes a receiving module 151 and a processing module 152; the receiving module 151 is configured to receive a first message, where the first message is sent by a first RB after detecting that a network topology to which a local terminal is accessed changes; the processing module 152 is configured to clear the corresponding MAC forwarding entry according to the first packet.

Optionally, the first packet is an MAC clear packet, where the MAC clear packet includes VLAN information, and the processing module is specifically configured to: and clearing the MAC forwarding table entry corresponding to the VLAN indicated by the VLAN information.

Optionally, the MAC clear packet may further include one or more MAC addresses or aliases, and the processing module is specifically configured to: and clearing all MAC forwarding table entries corresponding to the VLAN indicated by the VLAN information, wherein the MAC forwarding table entries comprise the MAC addresses or the MAC alias.

Optionally, the first packet is a TCN packet, and the processing module is specifically configured to:

in the STP or RSTP scene, removing MAC forwarding table entries in all VLANs added to an access port facing a local terminal; or,

and under the MSTP scene, according to the corresponding relation between the locally configured instance and the VLAN and the instance information contained in the TCN message, clearing the MAC forwarding table entry of the VLAN corresponding to the instance indicated by the instance information.

Optionally, the apparatus may further include:

and the sending module is used for sending the TCN message to other switch equipment in the same STP domain so that the other switch equipment can clear the local MAC forwarding table entry.

In this embodiment, after the network topology accessed by the local terminal changes, the first message is used to acquire the switching and clear the MAC forwarding table entry, so that the MAC forwarding table entry on the second RB device can be quickly cleared, and the TRILL network data traffic is triggered to be quickly converged.

Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for clearing Media Access Control (MAC) forwarding table entries, comprising:

a first routing bridge device RB detects that the network topology accessed by a local terminal changes;

the first RB sends a first message to a second RB through an RB channel RBridge channel, the first message is used for indicating that the second RB clears an MAC forwarding table item corresponding to a first virtual local area network VLAN indicated by the first message after receiving the first message, and the second RB is an RB at least provided with a second VLAN which is the same as the first RB.

2. The method of claim 1, wherein the detecting, by the first RB, that the network topology accessed by the local terminal has changed under a designated forwarder, AF, mechanism comprises:

the first RB detects that it is switched from non-AF to AF.

3. The method of claim 2, wherein the first packet is a MAC clear packet, and the MAC clear packet includes VLAN information indicating that the second RB clears a MAC forwarding entry of the first VLAN corresponding to the VLAN information.

4. The method of claim 3, wherein the MAC clear message further includes one or more MAC addresses or aliases, and is used to instruct the second RB to clear all MAC forwarding entries of the first VLAN corresponding to the VLAN information, where the MAC forwarding entries include the MAC addresses or aliases.

5. The method of claim 1, wherein under a first RB Spanning Tree Protocol (STP) root bridge mechanism, the first RB detecting that a network topology of a local terminal access is changed comprises:

and the first RB receives a topology change TCN message from an access port facing to a local terminal.

6. The method according to claim 5, wherein when the second RB and the first RB are located in the same STP domain, the first message is a TCN message, and instructs the second RB to remove a local MAC forwarding entry, wherein in an STP or rapid spanning tree protocol RSTP scenario, the first message instructs the second RB to remove MAC forwarding entries in all VLANs added to an access port facing a local terminal, and in a multi-instance spanning tree protocol MSTP scenario, the first message includes instance information, and instructs the second RB to remove a MAC forwarding entry of the first VLAN corresponding to the instance information.

7. The method of claim 5, wherein when the second RB is an RB outside an STP domain where the first RB is located, the first message is an MAC clear message, and the MAC clear message includes VLAN information indicating that the second RB clears an MAC forwarding entry of the first VLAN corresponding to the VLAN information.

8. The method of any of claims 1-7, wherein the MAC forwarding entry comprises a correspondence between a terminal MAC address and the alias of the first RB.

9. A method for clearing Media Access Control (MAC) forwarding table entries, comprising:

a second routing bridge device (RB) receives a first message through an RB channel (RBridge channel), wherein the first message is sent after the first RB detects that the network topology accessed by a local terminal changes, and the second RB is an RB configured with at least one second Virtual Local Area Network (VLAN) which is the same as the first RB;

and the second RB removes the MAC forwarding table corresponding to the first VLAN indicated by the first message according to the first message.

10. The method of claim 9, wherein the first packet is an MAC clear packet, the MAC clear packet includes VLAN information, and the clearing the MAC forwarding table entry corresponding to the first VLAN indicated by the first packet according to the first packet comprises:

and clearing the MAC forwarding table entry of the first VLAN corresponding to the VLAN information.

11. The method of claim 10, wherein the MAC clear message further includes one or more MAC addresses or aliases, and the clearing the MAC forwarding entry of the first VLAN corresponding to the VLAN information includes:

and clearing all MAC forwarding table entries of the first VLAN corresponding to the VLAN information, wherein the MAC forwarding table entries comprise the MAC addresses or the MAC forwarding table entries of the aliases.

12. The method according to claim 9, wherein the first packet is a topology change TCN packet, and the clearing, according to the first packet, the MAC forwarding table entry corresponding to the first VLAN indicated by the first packet comprises:

in the scene of a spanning tree protocol STP or a rapid spanning tree protocol RSTP, removing MAC forwarding table entries in all VLANs added to an access port facing a local terminal; or,

in a multi-instance spanning tree protocol (MSTP) scene, the TCN message contains instance information, and according to the corresponding relation between the locally configured instance and the VLAN and the instance information contained in the TCN message, the MAC forwarding table entry of the first VLAN corresponding to the instance indicated by the instance information is cleared.

13. The method of claim 12, further comprising:

and the second RB sends the TCN message to other switch equipment in the same STP domain so that the other switch equipment can clear local MAC forwarding table items.

14. An apparatus for clearing Media Access Control (MAC) forwarding entries, comprising:

a sending module, configured to send a first packet to a second routing bridge device RB via an RB channel RBridge channel, where the first packet is used to indicate that the second RB removes an MAC forwarding table entry corresponding to a first virtual local area network VLAN indicated by the first packet after receiving the first packet, and the second RB is an RB that is configured with at least one second VLAN that is the same as the first RB.

15. The device of claim 14, wherein the detection module is specifically configured to:

and after the device is detected to be changed from non-AF to AF under the appointed forwarder AF mechanism, determining that the network topology accessed by the local terminal is changed.

16. The apparatus according to claim 15, wherein the first packet sent by the sending module is an MAC clear packet, and the MAC clear packet includes VLAN information, and indicates the second RB to clear an MAC forwarding entry of the first VLAN corresponding to the VLAN information.

17. The device of claim 14, wherein the detection module is specifically configured to:

and under a first RB simulation spanning tree protocol STP root bridge mechanism, when receiving a TCN message from an access port facing a local terminal, determining that the network topology accessed by the terminal is switched.

18. The apparatus of claim 17,

the first message sent by the sending module is a topology change TCN message and indicates the second RB to clear local MAC forwarding table entries, wherein in the STP or RSTP scene, the first message indicates the second RB to clear the MAC forwarding table entries in all VLANs added to an access port facing a local terminal, and in the MSTP scene, the first message contains instance information and indicates the second RB to clear the MAC forwarding table entries of the first VLAN corresponding to the instance information; or,

the first message sent by the sending module is an MAC clearing message, the MAC clearing message contains VLAN information, and the second RB is instructed to clear the MAC forwarding table entry of the first VLAN corresponding to the VLAN information.

19. An apparatus for clearing Media Access Control (MAC) forwarding entries, comprising:

a receiving module, configured to receive a first packet via an RB channel, where the first packet is sent after a first routing bridge device RB detects that a network topology to which a local terminal is accessed changes;

and the processing module is used for clearing the MAC forwarding table entry corresponding to the first virtual local area network VLAN indicated by the first message according to the first message.

20. The device according to claim 19, wherein the first packet is an MAC clear packet, the MAC clear packet includes VLAN information, and the processing module is specifically configured to:

21. The device according to claim 19, wherein the first packet is a topology change TCN packet, and the processing module is specifically configured to:

and under the multi-instance spanning tree protocol (MSTP) scene, clearing the MAC forwarding table entry of the first VLAN corresponding to the instance indicated by the instance information according to the corresponding relation between the locally configured instance and the VLAN and the instance information contained in the TCN message.

22. The apparatus of claim 21, further comprising: